1. Field of the Invention
The present invention relates to a device for measuring optical characteristics of various kinds of liquid analyte with the use of an optical fiber. This device can measure the amount of light absorbed or scattered by a liquid analyte and can measure the amount of light fluorescently or chemically emitted from the liquid.
2. Description of the Related Art
Conventionally, there are two methods for measuring, with the use of an optical fiber, the amount of light fluorescently or chemically emitted from a liquid analyte. In one method, one end of the optical fiber is immersed directly into a liquid held in a vessel so as to irradiate the liquid with detection light. In the other method, an optically transparent container is additionally provided. A liquid analyte from the vessel is first transferred to the optically transparent container and then irradiated with detection light through the transparent wall of the container.
In the first method, the optical fiber is contaminated by the liquid. Although the second method eliminates contamination of the optical fiber, measurements are insufficiently accurate. Because the optical fiber is separated from the liquid by the thickness of the container wall, less light reaches the optical fiber, thereby lowering efficiency at which light is picked up.